1. Field of the Invention
Embodiments of this invention relate to a capacitive type touch screen panel.
2. Discussion of the Related Art
Along with the development of the electronics industry, display devices, such as a liquid crystal display, an electroluminescent display, and a plasma display panel having a quick response speed, low power consumption, and an excellent color reproduction rate, have been in the spotlight. The display devices are used for various electronic products such as televisions, monitors for computers, notebook computers, mobile telephones, display units for refrigerators, personal digital assistants, automated teller machines, and the like. In general, the display device interfaces with various input devices such as a keyboard, a mouse, and a digitizer. However, when a separate input device such as a keyboard, a mouse, or digitizer is used, user's dissatisfaction is increased because the user is required to know how to use the separate input device and the separate input device occupies space. Therefore, a convenient and simple input device that can reduce erroneous operation is needed. Also, there is a need for a touch screen panel in which a user can input information by directly contacting a screen with a finger or a pen.
Because the touch screen panel has a simple configuration, which minimizes erroneous operations, the user can perform an input action without using a separate input device, and can quickly and easily manipulate through contents displayed on a screen. Accordingly, the touch screen panel has been applied to various display devices.
Touch screen panels are classified into a resistive type, a capacitive type, an electromagnetic type according to a detection method of a touched portion. The resistive type touch screen panel determines a touched position by a voltage gradient according to a change of resistance in a state that a DC voltage is applied to metal electrodes formed on an upper plate or a lower plate. The capacitive type touch screen panel senses a touched position according to a difference in capacitance created in an upper or lower plate when the user physically contacts with a conductive film formed on the upper or lower plate. The electromagnetic type touch screen panel detects a touched portion by reading an LC value induced as an electromagnetic pen touches a conductive film.
Hereinafter, a related art capacitive type touch screen panel will be described with reference to FIGS. 1 and 2. FIG. 1 is a top plan view illustrating a related art capacitive type touch screen panel, and FIG. 2 is a cross-sectional view illustrating the touch screen panel taken along line I-I′ of FIG. 1.
Referring to FIGS. 1 and 2, the related art capacitive type touch screen panel includes an electrode forming part A, a routing wire forming part B, a pad forming part C.
The electrode forming part A is formed on a substrate 10 and includes a plurality of first electrode patterns 40 arranged in parallel in a first direction (for example, X-axis direction), a plurality of bridges 20 connecting neighboring first electrodes 40 each other, and a plurality of second electrode patterns 50 arranged in a second direction (for example, Y-axis direction) to cross over the first electrodes 21.
The routing wire forming part B is formed on the substrate 10 at positions outside the electrode forming part A and includes a plurality of first routing wires 61 connected to the plurality of first electrode patterns 40, respectively, and a plurality of second routing wires 63 connected to the plurality of second electrode patterns 50, respectively.
The pad forming part 60 includes a plurality of first pads 71 connected to the plurality of first electrode patterns 40 through the plurality of first routing wires 61, respectively, and a plurality of second pads 73 connected to the plurality of second electrodes 50 through the plurality of second routing wires 63, respectively.
The capacitive type touch screen panel also includes an insulation layer 30. The insulation layer 30 is formed on the substrate 10 on which the bridges 20 and the first and second routing wires 61 and 63 are formed, and electrically insulate the first electrode patterns 40 from the second electrode patterns 50. The insulation layer 30 includes first contact holes 33 exposing the bridges 20 and second contact holes 35 exposing the first and second routing wires 61 and 63.
However, in the related art capacitive type touch screen panel, the first and second routing wires 61 and 63 are formed to be overlapped with the first electrode patterns 40 or the second electrode patterns 50 only in the second contact holes 35 as shown in FIG. 2. That is, the first and second routing wires 61 and 63 are formed of a single metal layer in most region of the routing wire forming part B. The first and second routing wires 61 and 63 or the insulation layer 30 formed in the most region of the routing wire forming part B are easily scratched in panel fabricating process module fabricating process to manufacture a display device with the touch screen panel because they have a very low hardness. Accordingly, the first and second routing wires 61 and 63 may be shorted or opened due to the scratch. There is a problem that touch operation cannot be perceived when the first and second routing wires 61 and 63 are shorted or opened.